China has made a major breakthrough in the field of metro vehicle technology. On June 28th, China’s first (see note 1) standard metro train, developed by CRRC Corporation Limited, was rolled out in Zhengzhou. This marked a key step for China’s metro vehicles towards “standardization”.
Beginning in July 2019, CRRC (together with the China Association of Metros, metro companies, scientific research institutions and cooperative ventures) implemented a national series of standard metro train development and testing projects. The aim of these was to break through the core technology and create a “standardized” metro train platform specifically tailored to domestic demands. This was done by improving the degree of standardization and modularization in Chinese metro equipment and establishing a new domestic standard for urban rail equipment. After two years of technical research, the first Chinese standard metro train was rolled out. This was based on the Chinese standard, and made full use of the concepts of standardization, modularization and seriation, with completely independent intellectual property rights. “China standard” covered over 85% of equipment, and realized “9 processes and 2 upgrades”.
The 9 processes: 1. Key component localization. 2. Component standardization. 3. Component modularization. 4. System integration. 5. Functional configuration. 6. Vehicle standardization. 7. Product seriation. 8. Product modularization. 9. Industry standardization.
2 upgrades: 1. Safety upgrade. 2. Performance upgrade.
Among these components, metro gearboxes are an important constituent in standardized Chinese bogies for metro systems. These need to operate under variable loads and strong vibrations, leading to high requirements for safety and stability.
This gearbox by NGC was built in strict accordance with Chinese metro regulations, and combined NGC’s years of experience in design and manufacture. It makes use of the standard metro gearbox 120B platform. This gearbox is characterized by its light weight, low noise, long service life, high reliability, and good maintainability. The gearbox uses a number of advanced concepts:
1. Standardized, modularized, serialized, and integrated. The gearbox adheres to CRRC’s requirements for standardization of interface to current NGC platforms, realizing the customer’s needs. At the same time, 80% of the gearbox components are interchangeable with NGC’s existing standardized platform, and the localization rate is at 100%;
2. Unique gear modification technology, greatly improving the carrying capacity of the gear and significantly reducing noise, in order to meet the strictest requirements for service life and noise;
3. Nonlinear finite element analysis technology: the lightweight design improves the power density of the gearbox;
4. Full consideration of all domestic parts under bad weather conditions: tough housing materials are used, along with improved lubricant passage routes, to endow this gearbox with the ability to start up and operate at ambient temperatures of - 40 ℃ ~ 50 ℃;
5. Component design life of 30 years, with a maintenance-free operating distance of over 1.25 million kilometers.
At present, the China standard metro train Model A can handle speeds of 120 km/h, while Model B can operate smoothly at 80 km/h. NGC’s gearbox comes specially equipped for these different models, and are ready for dispatch.
As gearbox and transmission technology solutions experts, NGC have been deeply involved in transmission technology for more than 50 years. The company’s rail vehicle transmission products have been widely used in metros, trams, inter-city trains, high-speed rail vehicles and locomotives, as well as other areas of application. The company has established a number of long-term cooperation agreements with well-known manufacturers at home and abroad. Adhering to “zero defects in concept and process”, NGC is dedicated to providing safe, reliable, and quiet gear products for global customers, offering a full range of rail transit gear solutions. At the same time, the company has obtained both ISO/TS 22163:2017 (International Railway Industry Standard) quality system certification and CRCC railways product certification.
By means of optimized gearbox design technology, excellent sealing technology and effective control of the production process, NGC rail vehicle gearboxes highlight the company’s environmental friendliness. Today, NGC has more than 40,000 sets of metro gearboxes running in metro lines in China, North America, South America, Europe, Southeast Asia, South Africa and other places throughout the world. Our products have all been well received by customers.
Note 1: “The first China standard metro train” in the text is cited from a CCTV (CCTV13) news report at 15:46 June 28, 2021.